(1) Field of the Invention
The present invention relates generally to firearms and, more particularly, to an improved breech plug for a muzzle-loading firearm.
(2) Description of the Prior Art
Modern breech-loading firearms, such as rifles, include a barrel having an axial bore, a stock to support the barrel, and a receiver at the breech end of the barrel. The receiver is comprised of a housing which includes a chamber for insertion of a cartridge into the breech of the barrel, a means for firmly securing the cartridge in the breech of the barrel in a sealed and locked position, a firing pin to discharge the cartridge primer, a trigger to move the firing pin into engagement with the cartridge primer, and an ejector to remove the cartridge after firing.
Muzzle-loading rifles and other muzzle-loading firearms are also comprised of a barrel with an axial bore and a supporting stock. However, a muzzle-loading rifle is loaded by inserting a charge of powder, wadding and shot through the muzzle end of the barrel and tamping the charge securely into the breech end of the barrel. The powder is then ignited, e.g., by striking a percussion cap, which sends a flame, normally through a small opening or flame bore, into the breech of the barrel through a breech plug which separates the primer from the powder charge.
Muzzle-loading rifles have several disadvantages in comparison with breech-loading cartridge rifles. They are more difficult and time consuming to load, and require greater skill to use. Malfunctions are more common due to the relatively more complex firing mechanisms required to ignite the powder. Muzzle-loading rifles are effected by inclement weather, particularly rain and moisture which affects the powder and causes the rifle to misfire. Muzzle-loading rifles must also be cleaned thoroughly to prevent clogging and corrosion by the powder residue.
Despite these disadvantages, many hunters and firearms enthusiasts prefer to use muzzle-loading firearms, at least on some occasions, due to the nostalgia and the sport which the muzzle-loaders afford. In addition, many states allow a longer hunting season and special hunting areas for muzzle-loading firearms, due to the greater challenge provided and, consequently, the much smaller number of animals taken.
Various designs have been proposed for the construction of improved muzzle-loading rifles. For example, U.S. Pat. No. 4,700,499 to Knight discloses a muzzle loading rifle that uses a "nut cracker" type of action to fire a conventional percussion cap.
U.S. Pat. No. 3,780,464 to Anderson and U.S. Pat. No. 4,283,874 to Vaughan disclose mechanisms for replacing the flash hole structure in breech or muzzle loading firearms to allow firing with modern metallic cartridge primers. Both inventions use a cap covering to hold the primer in place until firing.
U.S. Pat. Nos. 4,227,330 and 4,232,468 to Chapin disclose a conversion plug that can be configured to be removably inserted into the breech of a breech loading firearm to convert the firearm into a muzzle loading type. The conversion plug includes a primer cap receiving chamber which communicates with the bore of the rifle through a flash hole.
U.S. Pat. Nos. 4,222,191 to Lee et al; U.S. Pat. No 4,437,249 to Brown et al; and U.S. Pat. No 5,010,677 to Carron all disclose variations of the Chapin type of conversion plug for converting a shotgun or rifle into a muzzle loader.
U.S. Pat. Nos. 5,511,334 and 5,642,583, issued to Ball et al., disclose a way to convert a modern breech lock, cartridge rifle into a rifle that can be used as a muzzle-loading rifle. The disclose of these patents are hereby incorporated by reference in their entirety. However, even in this design the flame bore extending through the breech plug can become clogged or corroded after repeated use. This may require that the entire breech plug be replaced at some expense.
Thus, there remains a need for a new and improved breech plug for a muzzle-loading rifle which can be more easily cleaned after use while, at the same time, utilizes a replaceable aperture adjacent to the firing chamber which can be easily replaced if damaged beyond repair.